The charge of an electron is $-1.6\times {10}^{-19}\mathrm{C}$. The value of free charge on Li⁺ ion will be

The charge of an electron is 1.6×10⁻¹⁹ coulombs. Li lose one electron to form  ${\mathrm{LI}}^{+}$ ion hence value of charge on  lithium  ion will be 1.6×10⁻¹⁹ coulombs.